Coach Leslie Frazier said running back Adrian Peterson "looks to be full strength" as he bounces back from taking a knee to the calf in the first half of last week's loss to the Lions.

As for linebacker E.J. Henderson, well, the coach sounded concerned about his middle linebacker's troublesome left knee as he spoke to reporters after today's practice.

"E.J.'s still a little sore," Frazier said. "We'll see how he does tomorrow, but we're expecting to play him. But how much we'll play him, we'll see."

According to the team's official injury report, Henderson was limited in practice and is listed as questionable. Safety Jamarca Sanford (thigh) had full participation but is the only other player listed as questionable.

Frazier said the team will decide Saturday whether to make backup middle linebacker Xavier Adibi active for Sunday's game at Kansas City. Weak-side linebacker Erin Henderson can also play middle linebacker, while Kenny Onatolu plays Erin's weak-side spot.

Because E.J. plays nearly every snap and is a leader on and off the field, it's tough on the Vikings to practice without him. Henderson missed two practices two weeks ago because of knee swelling and soreness. He was OK last week, but the problem resurfaced this week. He has yet to miss a game because of the injury.

"We count on him, especially in a game like this where they want to establish the run along with hit some plays in the passing game," Frazier said. "He's such a big part of what we do from a leadership standpoint as well as being a good football player. It's tough when he's not able to practice every day and we're a little bit in limbo about how much he'll be able to play on Sunday."

Dan Wiederer caught up with Henderson in the locker room and found a frustrated player hoping this doesn't become a weekly hurdle.

"It's the wear and tear, man," Henderson said. "It's definitely frustrating right now. I think the way we're looking at it is that it's early in the season so if it's something we can get our hands around and calm it down before it drags into midseason, the better we'll be."
Frazier said the decision to use defensive end Everson Griffen at linebacker in a three-man line wasn't made to help reduce E.J.'s snap count. In some of the three-man line formations, Griffen replaced E.J. when the Vikings went to six defensive backs.

"We were going to do that even if E.J. was healthy," Frazier said. "Going back to training camp wanting to look at Everson at linebacker with the idea that one day we could have a package together where he could do some different things."

Frazier said Peterson finished practice Friday without any issues with the calf. Peterson officially was listed as full participation for Friday's practice and probable for the game.

"He was fine today," Frazier said. "There was nothing he wasn't able to do."

Here's the rest of the official injury report: Asher Allen (toe), Tyrell Johnson (hip), Jim Kleinsasser (elbow), Chris Cook (groin) and Kevin Williams (foot) all had full participation in practice and are probable for the game.